The present disclosure relates loudspeakers and audio systems.
Large and small arrays of wide-bandwidth loudspeakers have been the standard for producing medium and high sound pressure levels for communications, presentations, concerts and performances demanding high fidelity for many years. Both large and small sound systems for commercial uses are found in movie theatres, board rooms, universities, night clubs, race tracks, stadiums and houses of worship—to name but a few applications. Such systems are commonly used to amplify an audio signal derived from a live or a recorded source that is controlled by an operator using an audio mixing system called an audio mixing console. The console is followed by a wide array of electronic equipment that results in the amplified audio signals radiating from arrays of loudspeakers directed toward an audience.
Early in the history of professional audio, two distinct loudspeaker types have been evident that are of interest. The most common has been a multi-way loudspeaker characterized by transducers of different frequency band assembled in a common enclosure. The second is the line array or column loudspeaker, characterized as a group of limited bandwidth transducers of a common frequency range, arrayed in a straight line in a long narrow enclosure. Engineers have utilized both types of loudspeaker types in several fundamentally different approaches to sound dispersion in larger applications, with the common goal of delivering sound more uniformly and with greater clarity to the listener. One approach has been to use a concentrated three dimensional group of loudspeakers, known alternately as a spherical array, a cluster or perhaps a point source. Where projecting sound from such a source is not feasible, another approach has been to distribute loudspeakers throughout the listening space.
In the past two decades, the principles of the simple line array have been more widely applied resulting in new variants of the two-way and three-way loudspeaker. In the example of the two-way loudspeaker, vertical arrays of enclosures have been configured to align vertical rows of low-frequency transducers symmetrically on either side of a centrally oriented high-frequency linear sound source. For the best performance, the high-frequency (HF) source is typically very narrow in the horizontal dimension and the vertical dimension ideally extends to the full height of the loudspeaker enclosure.